The present invention is directed toward an ice-cream dipping cabinet that provides increased visibility of the ice cream product while, at the same time, extending the product shelf life. Maximizing product visibility is an important. criterion in the design of merchandising display cases. However, this objective has been most difficult to achieve in the design of cabinets for displaying of refrigerated products, because both the conditioning apparatus and the insulated enclosure obstruct view.
This is particularly true in the case of the traditional ice-cream dipping cabinet. Typically, dipping cabinets are horizontal cabinets constructed with interior and exterior sheet metal skins surrounding an insulated core. Refrigerated coils, fastened to the inner skin, provide the cooling means for maintaining temperatures in the range of 0 to 10.degree.. The top of these cabinets is normally provided with a sneeze guard and translucent covers. Combined, these features allow only limited viewing of the product.
A principal reason that the aforementioned design has become conventional is that it provides a thermally stable environment, a condition which enhances product quality and increases shelf life. Frozen dairy products contain a high concentration of water and, even though at low temperature, water molecules tend to diffuse through and migrate out of the product. This diffusion is driven by vapor pressure differences which relate to temperatures in general, and dew point temperatures in particular. The greater the difference between the dew point of the product and its surroundings, the greater the diffusion rate and moisture loss. If the air surrounding the product is in motion, say by forced convection, the rate of loss is increased. This moisture migration degrades product quality.
Cyclical temperature variations also have a negative effect on ice-cream quality. At normal serving temperatures, the water in ice-cream is present in both solid and liquid states. Cyclical temperature changes cause melting and freezing with an accompanying agglomeration of ice crystals.
Hence, the traditional ice-cream cabinet has a "cold wall" construction. The inner surfaces of the cabinet are refrigerated. Conduction and natural convection are the principal means of heat transfer from the product. Air is not circulated, and the environment is stable. Moreover, the thermal inertia of the design dampens temperature variations. Both dew point temperature differences and cyclical variations are small, fulfilling the conditions that enhance product quality.
Conventional "cold wall" dipping cabinets have proven to be functionally satisfactory insofar as temperature variations are minimized. However, this conventional structure greatly restricts the customer's view of the product within the cabinet. Accordingly, there exists a need in the art for a dipping cabinet which retains the qualities of conventional dipping cabinets while readily permitting visualization of the food product stored therein.